This application discloses an indention which is related, generally and in various embodiments, to a self-scaling liquid containment system with one or more internal energy absorbing members.
There are a variety of liquid containers currently in use which hold fuels (gasoline, jet fuel, kerosene, oil, diesel, etc.) or other fluid (water, alcohol, solvent, lubricant, etc.). Depending on the liquid which the containers are to hold, the containers may be fabricated from plastic, aluminum, steel etc. For containers which are to bold fuel, such containers include, for example, free-standing fuel storage tanks, fuel tanks of vehicles, fuel transport vehicles, etc. In general, many of such had containers are constructed from metals (e.g., steel, aluminum, etc.) having nominal thicknesses and no special protection horn a high impact event and/or a high energy ballistic event. A simplified representation of a liquid container capable of holding fuel is shown in FIG. 1.
In many situations, especially in military-related situations, a breach or opening created through the wall of a standard fuel container such as, for example, a fuel tank, of a vehicle, can have disastrous consequences. Such consequences can range from the loss of valuable fuel to the ignition of the fuel and the explosion of the container/vehicle. In the case of a standard fuel container if the standard fuel container is subjected to a high impact event and/or a high energy ballistic event, it is not uncommon for the event to cause a breach or opening through a wall of the fuel container. The breach or opening leads to the rapid loss of fuel and possibly the ignition of the fuel and the explosion of the container/vehicle. Obviously, the breach or opening can pose a serious risk to the lives of people in the vicinity of the fuel container.
Various approaches have been utilized to reduce the risk of the negative consequences associated with a breach or opening through a liquid containers wall. Such approaches include, for example, spraying a protective coating over the exterior surface of the liquid container, surrounding the liquid container with ballistic plates, surrounding the liquid container with self-sealing panels and self-sealing cap members, etc.
For a given liquid container, although the above-described approaches have varying levels of success regarding the prevention and/or self-sealing of “entrance penetration wounds” to a wall of the liquid container, the respective approaches are often less successful regarding the prevention and/or self-sealing of “exit penetration wounds” to one or more walls of the liquid container.
In general, an entrance penetration wound to a wall of a given liquid container results in minimal deflection of the wall. When a projectile impacts the wall of the liquid container, the relatively low compressibility of the fluid within the liquid container operates to limit the “inward” deflection of the wall. As the projectile passes through the wall, any petalling resulting from the entrance penetration is typically directed into the liquid container and away from an external self-sealing coating. Thus, the breach or opening through the wall tends to be “clean” allowing any external protection (e.g., a self-sealing coating) to provide adequate reduction or elimination at fluid leakage.
In contrast to its performance regarding entrance wounds, it is significantly more difficult for an external self-sealing coating to rapidly provide a reduction in fluid leakage or completely seal m exit wound. When a projectile which has passed through a given wall of a liquid container and into the interior of the liquid container subsequently impacts another wall of the liquid container (or the given wall at a different location), the resulting “outward” deflection of the impacted wall is generally more severe than the previous “inward” deflection of the given wall.
There are multiple factors which can cause the “outward” deflection to be more severe than the associated “inward” deflection. For example, although the fluid within the liquid container operates to limit the “inward” deflection of the wall it does not operate to limit the “outward” deflection of the wall. Also, when the projectile impacts the fluid within the liquid container, a pressure wave is developed which travels through the fluid, and the traveling pressure wave operates to exert additional forces (e.g., hydro-dynamic ram) against the wall which can contribute to greater resultant damage at the exit wound. Additionally, projectile dynamics can also contribute to greater resultant damage at the exit wound. Non-spherical and ogive-shaped projectiles are very unstable as they travel through fluid. Due to this instability, these projectiles often impact tank walls in a tumbled or off-axis condition. When a projectile in a tumbled or oil-axis condition penetrates a given wall of the liquid container, the resulting opening in the wall tends to be in the shape of a large oblong hole.
Petalling resulting from the exit penetration is typically directed away from the liquid container and toward an external self-sealing coating. Cracking of the wall may also occur at the exit wound. The combination of deflection, petalling and cracking all create a wound that is significantly larger and therefore more difficult to rapidly and completely seal than a typical entrance wound.
One approach to reducing die size of a potential exit wound has been to increase the thickness of the wall of the liquid container to absorb/dissipate greater amounts of energy upon, projectile impact. The energy required for a projectile to penetrate a wall of the liquid container is proportional to the thickness of the wall. By increasing the thickness of the wall, the amount of energy introduced into the liquid container by tire projectile is reduced, and the amount of energy subsequently applied to the exit wound is reduced. However, increased wall thickness alone is undesirable as it adds weight and reduces the volumetric capacity of the liquid container (for the same overall size).
Some liquid containers include interior features, which although not specifically designed to eliminate or reduce exit penetrations by increased energy absorption, do operate to potentially limit the amount of energy applied to an exit wound. Such interior features include, for example, a slosh baffle, a chamber baffle, a diaphragm, a bladder, etc.
Regarding internal slosh baffles, one or more slosh baffles have been mounted strategically within a fuel tank to mitigate fluid oscillation due to slosh, and generally have been positioned within the fuel tank to handle areas of excess shad motion. Slosh baffles are typically fabricated irons a material which is the same as or similar to the wall of the fuel tank. While such slosh baffles will absorb/dissipate some of the energy from a projectile passing through them, they are not constructed with the sufficient thickness, hardness, toughness, etc, to have the capability to absorb/dissipate enough of the projectile's energy to meaningfully reduce the projectile's ability to create a damaging exit penetration wound.
Regarding internal chamber baffles, one or more chamber baffles nave been mounted strategically within a fuel tank to create separated chambers within the fuel tank. The positioning of the chamber baffles have varied from application to application based on the chamber separation requirements. Chamber baffles are typically fabricated from a material which is the same as or similar to the wall of the fuel tank. While such chamber baffles will absorb/dissipate some of the energy from a projectile passing through them, they are not constructed with the sufficient thickness, hardness, toughness, etc. to have the capability to absorb/dissipate enough of the projectile's energy to meaningfully reduce the projectile's ability to create a damaging exit penetration wound.
Regarding interior diaphragms, one or more diaphragms have been positioned strategically within a feel tank to control internal pressures in individual chambers within the fuel tank. The diaphragms are typically fabricated from a compliant material. While such diaphragms will absorb/dissipate some of the energy from a projectile passing through them, they are not constructed with the sufficient thickness, hardness, toughness, etc, to have the capability to absorb/dissipate enough of the projectile's energy to meaningfully reduce the projectile's ability to create a damaging exit penetration wound.
Regarding inferior bladders, one or more bladders have been positioned within a liquid container and operate to contain, a liquid or fluid. The bladders are typically fabricated from a compliant material. While such bladders will absorb/dissipate some of the energy from a projectile passing through them, they are not constructed with the sufficient thickness, hardness, toughness, etc. to have the capability to absorb/dissipate enough of the projectile's energy to meaningfully reduce the projectile's ability to create a damaging exit penetration wound.